1. Field of the Invention
The present invention relates to a stitch data producing system for producing stitch data necessary for embroidering a desired pattern on a workpiece by an embroidery machine.
2. Description of the Related Art
A known embroidery machine capable of automatically embroidering a workpiece operates according to stitch data specifying an X-direction movement and a Y-direction movement of the workpiece for each stitch. The applicant of the present application developed a stitch data producing system described in U.S. Pat. Nos. 4,526,116 and 4,849,902. This stitch data producing system is constructed by connecting an image scanner, a keyboard, a disk drive, a CRT and the like to a personal computer. The stitch data producing system produces stitch data from a hand-drawn or printed picture, such as an original pattern A or a shooting star as shown in FIG. 5.
When producing stitch data by the stitch data producing system, the image scanner scans the original pattern to produce original image data corresponding to the original pattern. The original pattern is segmented on the basis of the original image data into a plurality of continuous individual component patterns (embroidering regions). As shown by way of example in FIGS. 6A, 6B, 6C and 6D, the original pattern A of FIG. 5 is decomposed into an embroidering region B for a star, and embroidering regions C, D and E respectively for three streaks. Contour data defining the contour of each embroidering region is determined, and stitch data for each embroidering region is produced.
The component pattern included in each embroidering region is embroidered by a satin stitching method (FIG. 7A), a fill stitching method ("Tatami" stitching method FIG. 7B), a running stitching method (FIG. 7C), a zigzag stitching method or the like, and different stitching methods produce embroideries having different appearances. Therefore, the stitch data must include data specifying a stitching method. The known stitch data producing system specifies only a single stitching method, such as a satin stitching method for each embroidering region or allows the operator to specify a stitching method for each embroidering region.
However, if stitch data is produced by a stitch data producing system that specifies only a single stitching method, for example, a satin stitching method, a component pattern included in an elongate embroidering region or a large embroidering region, though suitable for being formed by zigzag stitches or fill stitches ("Tatami" stitches), is formed by satin stitches for lack of an alternative. If stitch data is produced by a stitch data producing system requiring the operator to specify a stitching method, the operator is required to specify a desired stitching method for each region, and if the operator is unskilled or inexperienced, the operator may be unable to specify a suitable stitching method.